Apparatus for the removal of water, liquors, or other liquids from soaked masses of fibrous materials



Dec; 19, 1944. F. SCHUMACHER 2,365,653 APPARATUS FOR THE REMOVAL OFWATER, LIQUQRS OR OTHER LIQUIDS FROM SOAKED MASSES OF FIBROUS MATERIALSI I Filed March 14, 194], 2. Sheets-Sheet l 3 F J, INVE%TOR. 1 I! ZlZi/Zlll 6V. @25 BY C 7 7 Dec. 19, 1944. F. SCHUMACHER 2,365,658APPARATUS F THE REMOVAL OF WATE LIQUORS OTHER LIQUIDS M SOAKED MASSES OFF ROUS MAT ALS Filed March 14, 1941 2 Sheets-Sheet 2 IN VENTOR.

M ATTORNEY Patente Dec. 19, 1944 APPARATUS FOR THE .LIQUORS, R OTREMOVAL OF WATER, HER LIQUIDS FROM SOAKED MASSES 0F FIBROUS MATERIALSFritz Schumaeher, Oberlenningen, Wurttemberg, Germany, assignor toAmerican Voith Contact Co. Inc., New York, N. Y.,

York

a corporation of New Application March 14, 1941, Serial No. 383,415

In Germany June 20, 1939 v 1 Claim.. (Cl. 100-37) This invention relatesto anew and useful improvement in apparatus for the removal of water,

I liquors or other liquids from soaked masses of fibrous materials, suchas cellulose, mechanical wood pulp, or the like, to thicken thelatter,and has for its object to provide a device of this characterwhich is continuous in operation with high liquid-removal efiiciency andwithout damage to the fibers of the material being treated.

The invention consists in introducing the fibrous material between theperiphery of a rotating perforated drum and an endless belt which partlysurrounds the latter; and gradually increasing the pressure of the beltagainst the periphery of the drum toward the end of the belt run,whereby the liquid is more moved from the fibrous material.

The invention also resides in a cylindrical drum provided on its outerperiphery with a plurality of annular grooves, the bottom of whichcommunicate with the interior of the drum through the medium oftransverse openings.

With the above and other objects in View which will appear as thedescription proceeds, the invention resides in the novel featurehereinafter set forth, illustrated in the accompanying drawings and moreparticularly pointed out in the appended claim.

Referring to the drawings in which numbers of like character indicatesimilar parts throughout the several views, I I

Fig. 1 is a diagrammatic end view of the apparatus with the drum shownin cross-section, and illustrating the arrangement of the guide andcompression rollers for the endless belt, the washing device, and adrive for the drum.

Fig. 2 is a view similar to Fig. 1 but showing a drive connection forthe endless belt instead of (a drive for the drum shown in Fig. 1.

Fig. 3 is a fragmentary detailed view of the Fig. 4 is an enlargedhorizontal sectional view of a portion of the drum shown in Fig. 3.

Fig. 5 is a diagrammatic view wherein the endless belt forms a feedingconveyor for the material to the cylindrical drum, said drum beingshownin section.

Fig. 6 is a view similar to Fig. 5 having preliminary water-removalmeans in the conveyor completely rerun of the endless belt.

Fig. 7 is a diagrammatic view wherein the endless belt forms a deliveryconveyor for the treated material leaving the periphery of the drum, and

E18. 8 is a view similar to Fig. 7 but including supplemental waterremoving means in the de- 'livery conveyor run of the endless belt.

In the drawings, a hollow rotatable perforated cylindrical member ordrum I, having end shaft portions la (Fig. 3) is rotatably supported insuitable bearings, not shown. An endless member or belt 2, partiallysurrounds the drum I and is guided over rollers 3, 4,-5, 6 and 1, ofwhich rollers 5 and I are preferably designed as tension rollers fortaking up any slack in the belt 2. Along the inner run of the belt 2,compression rollers 8, 9, III, II, and I2 are provided, whosecompression may be adjusted whereby the belt 2 is .forced against thedrum I with a gradually increasing pressure from the compression roller8 to the compression roller I2, as clearly shown in Fig. 1. It willbeseen in the drawings that the space between the belt 2 and the drum I,is larger at the entrance roller 3 than at the discharge roller 1, theentrance end having more water than the discharge end, the compressionrollers bein correspondingly adjusted.

- By this arrangement of guide rollers and compression rollers, the belt2 encircles the drum I for approximately of its circumference.

Drum I is rotated by any suitable means such as belts, gear wheels,etc., that?" shown in the drawings being a worm shaft 26 driven from asuitable source of power, not shown, said shaft meshing with acomplementary gear 26a on the shaft lajEof I to drive the latter in thedirectionof. the arrow shown in Fig. 1. Due to the frictional engagementof the belt 2 with the drum I, rotation of the drum by the driving meansabove described moves the endless belt 2 in the same direction sothatthe material to be treated entering the inner run of the belt 2adjacent the guide roller 3 is gradually compressed to remove the watertherefrom.

Any foreign matter or impurities collecting on c the belt 2 can beremoved by a scraping and washing device cooperating with the outer runof the belt 2 and comprising a number of pipes I3 for spraying jets ofwater against the belt, and brush rollers II for loosening anyencrustations so that the same can be washed by'the spraying jets ofwater. The cleansing water runs off the belt 2 and is collected in thetrough I5 from whence it can be conducted to any suitable point.

The cylindrical drum as shown in Figs. 3 and 4 is provided about itsperiphery with a series of circumferential grooves 33 in the bottom ofeach of which are a plurality of apertures 34 communicating with theinterior of the drum I.

Having described the construction of one embodiment of my invention, itsoperation is as follows:

The soaked fibrous material enters the inner run of the endless belt 2adjacent the guide roller 3 where the belt is spaced a predetermineddistance from the periphery of the drum to form an entrance.

As the fibrous material travels about the periphery of thedrum I, theinner run of the belt 2 compresses said material into a layer to expelthe water therefrom into the apertures 34 and into the interior of thedrum I from whence the water flows through outlet openings in the endfaces of the drum. During this operation, on the first quadrant of thedrum I, the layer of material moves downwardly and water will flow inabundant quantity into the interior of the drum through theabove-mentioned apertures 34. The second quadrant of the drumcircumference, or the bottom thereof will be covered in part on theinside by the water removed from the material during the first quadrant;however, the gradually increasing pressure of the compression rollers 8and I compresses the layer of the fibrous materials sufiiciently toprevent such water from becoming reabsorbed by the layer. On the thirdor last operation quadrant of the drum the layer of material moves in anascending direction and is further compressed between compressionrollers II and I2 pressing the belt 2 against the periphery of the druml. After the layer of the material passes compression roller I2, thepressure thereon is reduced to that pressure exerted by the tension onthe belt 2; consequently this drop in pressure allows the layer ofmaterial to expand prior to being removed at the upper run of the beltadjacent the roller 1. During this upward travel, due to the annulargrooves 33 on the drum I, the layer of fibrous material does not comeinto contact with the apertures 34 so that should there be any water insaid apertures due to adhesion, it cannot come in contact with the layerof material to be reabsorbed thereby during expansion of said layerwhich occurs between compression roller I2 and roller 1. Furthermore,the grooves 33 in the upward travel of the drum I form downwardlydirected channels betwen the individual apertures 34, in which channelsthe water pressed out of the layer flows downwardly and finally isdriven into the interior of the drum I through apertures 34. It willthus be seen that at the point of removal of the treated layer, theannular grooves 33 are substantially free from water so that no watercan return into said layer.

While in the foregoing form of the invention the drum 1 has been themember to be driven from a suitable source of power, movement of theendless belt 2 having been dependent upon the frictional engagement ofthe belt with the drum, it may be desirable and advantageous to connectthe driving means to the belt 2 instead of to the drum as shown inFig, 1. Such an arrangement is shown in Fig. 2, where the tension rollerl of Fig. 1 at the discharge end of the belt run is replaced by adriving roller 21 preferably of larger diameter than the guide andtension rollers 3, 4, 5, and 6, to provide a larger traction surface forthe belt. Roller 21 may be driven from any suitable source and by anysuitable belt or gearing arrangement, such for example as a motor Mdriving belt 29 which runs over the shaft 28 of the driving roller 21.If desired, the driving roller 21 may be rotated by a worm shaftarrangement similar to that shown in Fig. 1 for the drum I. As in theform heretofore described in connection with Fig. 1, compression rollers8, 3, III, II and I2 are provided for forcing the inner run of the belt2 -against the periphery of the drum I with a gradually increasingpressure.

With this arrangement, the endless belt 2 is positively driven from thedischarge end of the run about the periphery of the drum I and istensioned in a uniform manner between the rollers 3 and 21, therebyeliminating the possibility of folds forming in the belt 2 which maydevelop when the drum is the member being driven due to the unevencompression about the drum and the consequent uneven traction tension.

An arrangement of guide and tension rollers for the endless belt wherebya portion of the belt may be used as a conveying means for the materialto be treated, is shown in Fig. 5. In this arrangement, the outer run ofthe belt 2a extends from rollers 6a, 5a, and 4a, and instead of runningdirectly over the roller 3a adjacent the periphery of the drum Ia forthe beginning of the inner run of the belt, it is led to a roller I6located a predetermined distance away from the periphery of the drum Ia.From roller I6 the belt is conducted over roller 3a so that there isformed between rollers I6 and 3a a horizontally extending run I8 in thenature of a supply conveyor.

To remove some of the water from the material prior to being compressedbetween the drum and the inner run of the endless belt, pairs of rollersI9 and 20 as shown in Fig. 6, have the conveyor run I8 of the belt passbetween them.

To form a horizontal conveyor run 22 for the treated layer of materialdischarged from the periphery of the drum lb, the endless belt 2b isguided over rollers 3b, 4b, 5b, 6b and lb, and adjacent the dischargeend of the inner run about the drum II), the belt is led away from theroller lb to a roller 2| disposed in substantially the same horizontalplane as roller lb and located a predetermined distance away therefromas shown in Figure 7. From roller 2 I, the outer run of the belt 2b isguided over rollers 6b, 5b, 4b and 3b from which last-named roller itbegins its inner run in engagement, with the periphery of the drum I bwhich extends to the roller lb.

To further remove water from the layer of material after being treatedon the drum Ib, rollers 23, 24, and 25 as shown in Fig. 8, have theconveyor run pass between them, so that the material conveyed by saidconveyor run 22 is further compressed between the rollers 23, 24 and 25.

The relation of the belt to the drum as shown in the drawings of Figures5, 6, 7 and 8 are diagrammatic, and in practice of course show thegeneral relationship as shown in Figures 1 and 2.

A device constructed in accordance with the present invention, isespecially advantageous in respect to removing continuously water fromfibrous materials which possess fairly great initial thickness, such forexample, digestor materials and the like. pressure to which the layer ofmaterial is subjected may be varied to suit different conditions ofoperation, and the elastic pressure of the belt does not injure thefibers. Th parts are accessible, the pressure of the belt can bemaintained constant. In the suction-cell or pressure filters heretoforeused for th removal of water from fibrous materials and the like, theonly materials which could be treated had at most a density of 1.5%.

Furthermore, the water-removal On the other hand, with the presentinaccepts vention', materials having a density of as high as 12% admitof being freed from water without difficulty, and even up to drycontents of 40% and over. The apparatus is also adaptable to thepressing out of acid, caustic solutions and the like and is particularlysuited for the removal of water from paper pulps which have to be washedrepeatedly, that where water has to be removed again and again afterrepeated washings with liquid. The pressure of the rollers increasingtowards the material escape end makes it possible to overcome thecapillary forces, which increase as the water has been removed, andwhich forces hold the water fast between the fibers, and bring about anextensive removal of the water. The grooves in the cylinder assist in amore extensive freeing of the material from the water. These groovesbecome important since the water forcing operation corresponds only to atravel of about of the circumference of the cylinder. In the grooveconstruction in accordance with the invention, the layer of fibers doesnot come directly in contact with th upper edges of the individualboreholes; accordingly this suction effect does not occur at the abatingof the pressing pressure. Besides that, however, these groovesconstitute downwardly directed channels between the individual holes, inwhich channels the water that has been pressed out of the layer offibers can collect and, contrary to the slow upward movement of thispart of the cylinder, can fiow off downward and emerge into the interiorof the cylinder from the holes that are situated lower down. Thus itcomes to pass that at the point of removal of the layer of fibers thegrooves in the immediate vicinity thereof are practically free fromwater and that therefore a return of the already pressed-out water intothe layer can no longer take place.

The removal of water may be effected in this by means of belts, gearwheels, worm drive, or the a like and carries along by friction theendless belt which partially surrounds it. Since this arrangement,however, makes the endless belt dependent upon the adhesion to thecylinder, and since the belt, in traversing the interval between thecylinder and the guide rollers, tensing rollers, and adpression rollers,may show a tendency to the forming of folds in consequence of unequallyacti'ng slippage, there is provided the further arrangement of drivingthe endless belt or/and by means of a guide roller which is fashioned asa driving roller and which advantageously is situated as close aspossible to the discharge of the material. Thereby the endless belt, inits partial surrounding of the sieve drum from the entrance of thematerial to its escape, is made into a uniformly drawn strip whichdistributes the traction tension uniformly during the water-removalprocess and obviatescongestions of the fibrous material as a result ofslackening of the band, by which means a uniform removal of water isattained. This arrangement has a favorable effect,

above all, also with respect to the adpression rollers. Instead of andtogether with perforating the drum, the belt might be perforated.

While the foregoing invention has been described in connection with theremoval of water from fibrous materials, it is to be borne in mind thatthe invention is by no means intended to be limited to this particularapplication, as the device will operate with equal efficiency to removeacids, caustic solutions, liquors, or any other liquids from fibrousmaterials. In using the device for removing water, th endless belt ispreferably constructed of material which is water repellent, such asrubber and the like, but it will be understood that for treating fibrousmaterials containing acids or other strong liquids, the endless beltshould be constructed of materials which will resist the deleteriouseffects of such acids and strong liquors.

From the foregoing it is believed that the construction and advantagesof the present invention may be readily understood by those skilled inthe art without further description, it being borne in mind thatnumerous changes may be made in the details disclosed without departingfrom the spirit of the invention as set out in the following claim.

What is claimed and desired to be secured by Letters Patent is:

In an apparatus for treating fibrous liquid material to remove liquidtherefrom, the combination of a hollow rotatable cylindrical member withan axis horizontally disposed, having a series of annular groovesextending circumferentially about the periphery of said member andhaving a series of apertures in the bottom of said grooves opening incommunication with the interior of said cylindrical member, rollers, oneat each side of the cylinder and having their axes above the axis of thcylinder, an endless impervious belt member passing over said rollersand having an inner run portion partially surrounding the peripheralportion of said cylindrical member, said surrounding portlon having itsdischarge part in contact with the cylindrical member, the remainingpart spaced therefrom with its entrance part spaced th greatest distancefrom said cylindrical member the space between the cylindrical memher.and the belt member at the entrance and discharge ends being above theaxis of said cylindrical member forming a hydrostatic head to enablepressure and gravity to act onthe intervening fluid against said member,means for driving one of said members to move the other by frictionalengagement between the contacting parts of said members, and a pluralityof compression rollers acting on the surrounding belt portion forforcing the material between the members into

